This invention relates to an interface apparatus for use with a continuous mechanical volume ventilator and an intrapulmonary percussive ventilator and combination thereof and method.
It is well known that it is necessary to employ mechanical pulmonary assistance or control to support life in many situations. However, it has recently come to the attention of the medical field that there is an increasing incidence of major life-threatening barotrauma within the patient population receiving such cardiopulmonary assistance. Much of the blame on such barotrauma has been focused upon the abrupt dissecting phasic intrapulomary deliveries of programmed tidal exchanges delivered with major proximal/distal pressure gradients into the pulmonary structures of the patient. Clinical remedies for this barotrauma have been directed towards decreasing the programmed tidal volume delivery with an associated decrease in the inspiratory flow rate. Additionally suggestions have been made that the lungs of the patient should be stabilized with continuous positive end expiratory pressure to prevent peripheral (small) airway collapse, following each successive lung re-inflation associated with each tidal delivery (breath). In connection with such barotrauma it has been believed that peripheral intra-airway abrasion has been caused by the unrelenting tidal induced closure and re-inflation of small terminal pulmonary airways (which closed during the expiratory phase of the continuous mechanical ventilation); as the dilating inspiratory intrapulmonary pressure rises decayed during the expiratory phase of the mechanical ventilation, only to again be re-expanded during the next inspiratory tidal delivery. This abrasive opening and closing can occur as frequently as 18,000 times per day. Such mechanically induced lung damage required increasing oxygen concentrations in addition to the continuous mechanical ventilatory programming, which increases the onset of respiratory distress syndromes in both infant and adult patients receiving cardiopulmonary care. In addition it has been found that the reduction of tidal volumes to overcome barotrauma has increased the incidence of atelectasis and hypo-ventilation almost directly in proportion to the decrease in tidal volume delivery.
Ventilators are available which provide volumetric diffusive respiration which resolve most if not all of the ventillary compromises hereinbefore described causing barotrauma. However, there are many volume/pressure ventilators presently in service which do not have such capabilities and which represent major capital investments by hospitals and other medical facilities. There is therefore a need for an apparatus and method which makes it possible to utilize these volume/pressure ventilators now in the field to overcome or substantially eliminate the incidence of life-threatening barotrauma in patients receiving mechanical cardiopulmonary assistance.
In general, it is an object of the present invention to provide an interface apparatus for use with volume/pressure ventilators now in the field and an intrapulmonary percussive ventilator to overcome or substantially decrease the incidence of major life-threatening barotrauma in patients receiving mechanical cardiopulmonary assistance and a combination thereof and a method for managing such cardiopulmonary assistance of patients.
Another object of the invention is to provide an interface apparatus of the above character which can be readily integrated with existing volume/pressure ventilators.
Another object of the invention is to provide an interface apparatus and a combination incorporating the same which can be readily integrated with commercially available accessories.
Another object of the invention is to provide an interface apparatus of the above character which can be economically manufactured.